Grazing effect on different forage species in yield of soybean-pasture succession

Abstract

Integrated crop-livestock systems play a crucial hole on sustainable intensification due simultaneous increase the land use efficiency and minimize nutrient leaching due an intensification of nutrient cycling. However, these benefits depend on a good planning and management of the production system. The main objective of this study was to investigate biomass composition, soybean yield and beef cattle performance using three distinct forage cultivars within two cropping systems: Integrated Crop-Livestock System (ICLS) and the Pure Crop System (CS). The three forage cultivars used were: Urochloa ruziziensis, Urochloa brizantha cv. Xaraés, and Megathyrsus maximus cv. BRS Quênia. The experimental area was split into 24 plots, with each plot assigned one of the cropping systems and a specific forage cultivar. The ICLS involved soybean cultivation during spring-summer followed by cattle grazing during the autumn-winter. Conversely, the CS functioned as a pure crop system, utilizing soybean cultivation alongside forage as a cover crop. Soybean yield did not differ between ICLS and CS, neither between forage cultivars (4110 ± 627.0 kg ha−1). Animal performance did not differ between forage cultivars, resulting in average daily gain equals to 0.538 ± 0.316 kg of BW day−1. Animal production per area also was not affected by forage cultivars, yielding 145.0 ± 56.8 kg of BW ha−1. For comparison between systems, beef cattle production was converted in soybean equivalent based on commodities values. ICLS proportionated an increment of 624 ± 135 kg ha−1 per year of soybean equivalent yield, representing 15% increase in land use efficiency compared to the CS system. Therefore, beef cattle grazing in off-season of cash crops can enhance the sustainable intensification of food production. The forage species choice seems not be a paramount question for this model of ICLS.

Keywords

• Animal production
• Cerrado
• Crop-livestock integrated system
• Nutrient cycling